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BRIEF OVERVIEW
Sea turtles are large, air-breathing reptiles that inhabit tropical and
subtropical seas throughout the world. Their shells consist of an upper
part (carapace) and a lower section (plastron). Hard scales (or scutes)
cover all but the leatherback, and the number and arrangement of these
scutes can be used to determine the species.
Sea turtles come in many different sizes, shapes and colors. The Olive
Ridley is usually less than 100 pounds, while the leatherback typically
ranges from 650 to 1,300 pounds! The upper shell, or carapace, of each
sea turtle species ranges in length, color, shape and arrangement of
scales.
Sea turtles do not have teeth, but their jaws have modified "beaks"
suited to their particular diet. They do not have visible ears but have
eardrums covered by skin. They hear best at low frequencies, and their
sense of smell is excellent. Their vision underwater is good, but they
are nearsighted out of water. Their streamlined bodies and large
flippers make them remarkably adapted to life at sea. However, sea
turtles maintain close ties to land.
Females must come ashore to lay their eggs in the sand; therefore, all
sea turtles begin their lives as tiny hatchlings on land. Research on
marine turtles has uncovered many facts about these ancient creatures.
Most of this research has been focused on nesting females and hatchlings
emerging from the nest, largely because they are the easiest to find and
study. There are many nesting sites in the Bahamas which need to be
protected.
Thousands of sea turtles around the world have been tagged to help
collect information about their growth rates, reproductive cycles and
migration routes. After decades of studying sea turtles, much has been
learned. In the Bahamas this tagging takes place at Union Creek in
Andros. However, many mysteries still remain.
SEA TURTLES & HUMANS
Sea turtles have long fascinated people and have figured prominently in
the mythology and folklore of many cultures. In the Miskito Cays off the
eastern coast of Nicaragua, the story of a kind “Turtle Mother,” still
lingers. Unfortunately, the spiritual significance of sea turtles has
not saved them from being exploited for both food and for profit.
Millions of sea turtles once roamed the earth’s oceans, but now only a
fraction remain.
REPRODUCTION
Only females come ashore to nest; males rarely return to land after
crawling into the sea as hatchlings. Most females return to nest on the
beach where they were born (natal beach). Nesting seasons occur at
different times around the world. In the U.S., nesting occurs from April
through October. Most females nest at least twice during each mating
season; some may nest up to ten times in a season. A female will not
nest in consecutive years, typically skipping one or two years before
returning.
GROWTH & DEVELOPMENT
Researchers do not yet know how long baby turtles spend in the open sea,
or exactly where they go. It is theorized that they spend their
earliest, most vulnerable years floating around the sea in giant beds of
sargasso weeds, where they do little more than eat and grow. Once
turtles reach dinner-plate size, they appear at feeding grounds in
nearshore waters. They grow slowly and take between 15 and 50 years to
reach reproductive maturity, depending on the species. There is no way
to determine the age of a sea turtle from its physical appearance. It is
theorized that some species can live over 100 years.
STATUS OF THE SPECIES
The earliest known sea turtle fossils are about 150 million years old.
In groups too numerous to count, they once navigated throughout the
world's oceans. But in just the past 100 years, demand for turtle meat,
eggs, skin and colorful shells has dwindled their populations.
Destruction of feeding and nesting habitats and pollution of the world’s
oceans are all taking a serious toll on remaining sea turtle
populations. Many breeding populations have already become extinct, and
entire species are being wiped out. There could be a time in the near
future when sea turtles are just an oddity found only in aquariums and
natural history museums — unless action is taken today.
HOW YOU CAN HELP
There are many things each of us can do to help sea turtles survive.
First, we must remember that we share the oceans and the beaches with
many other species. Second, become informed about the things that are
killing sea turtles or destroying their habitat. Elected officials and
other leaders are making decision on issues that affect sea turtles
almost every day. As an informed citizen, you have the power to
influence the outcome of these issues by making your voice heard. One
way to keep informed about important issues is to join and support
groups like the Bahamas Sea Turtle Conservation Group, which monitor issues and encourage
their members to get involved.
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